#include <stdio.h>
#include <stdlib.h>

int main() {
	int a,b,c;
	scanf("%d %d",&a,&b);
	c=a%b;
	while(c!=0)
	{
		a=b;
		b=c;
		c=a%b;	
	}
	printf("%d",b);//将除数输出 
	return 0;
}
